The use of a bow and arrow in lieu of a rifle, shotgun, or the like, in the hunting of game has become increasingly popular in recent years. Many of the game hunters practicing bow and arrow hunting have found the use of a broadhead-type arrow achieves more efficient results, particularly in the hunting of relatively large game. The usual presently available broadhead-type arrow has certain disadvantages in that the speed, distance, and the accuracy of flight of the arrow shaft through the air is frequently adversely affected by the structural configuration of the arrowhead. In addition, there are certain legal requirements setting forth the conditions under which the use and structure of the broadhead-type arrows must comply.
Many attempts have been made to solve the problems encountered with the use of the broadhead-type arrow, such as shown in the Chandler U.S. Pat. No. 2,289,284, issued Jul. 7, 1942, and entitled “Interchangeable Arrowhead;” Recker U.S. Pat. No. 2,753,643, issued Jul. 10, 1956, and entitled “Fishing Arrow;” Grissinger U.S. Pat. No. 2,937,873, issued May 24, 1960, and entitled “Hunting Head for an Arrow or the Like;” Richter U.S. Pat. No. 2,940,758, issued Jun. 14, 1960, and entitled “Arrowhead;” Yurchich U.S. Pat. No. 3,014,305, issued Dec. 26, 1961, and entitled “Arrowhead for Bow Fishing;” Swails U.S. Pat. No. 3,036,396, issued May 29, 1962, and entitled “Retractable Arrow;” McKinzie U.S. Pat. No. 3,138,383, issued Jun. 23, 1964, and entitled “Dual Purpose Arrow Head;” Lint U.S. Pat. No. 3,168,313, issued Feb. 2, 1965, and entitled “Hunting Arrowhead with Retractable Barb;” and Hendricks U.S. Pat. No. 3,600,835, issued Aug. 24, 1971, and entitled “Spear Head with Swingable Barb.” Other configurations are also known.
Most prior art broadheads have straight blades in-line with the arrow shaft, and rotate fixedly with the arrow shaft in flight until they come in contact with the target. Specifically, standard fixed inserts for receiving broadheads are designed to be glued into a tubular arrow shaft. Such inserts have internal threads, so that the broadhead, or other types of practice and hunting arrow tips, can be utilized and interchanged. Once the broadhead has been screwed into the insert, the broadhead is fixed or stationary, and thus, rotates only as the arrow rotates in flight. Disadvantageously, when such fixed broadheads impact or contact the target, the arrow as a whole is forced to stop spinning, tears the target upon entry, and thereafter cuts straight through the target without the assistance of any rotational force or inertia, thereby significantly and detrimentally reducing the overall efficiency of the penetrating and cutting action.
Although broadheads having curved blades are available, such broadheads typically possess a pitch too great or too small to effectively penetrate the targeted medium, or often contribute to the skewed flight and/or trajectory of an arrow equipped therewith. More specifically, although a curved-blade broadhead having a large pitch corresponds to an equally large linear displacement of the broadhead through a targeted medium, arrows equipped with such broadheads often experience large deviances from the expected path of trajectory; that is, the expected flight path of the arrow is largely skewed from the selected target, especially when traveling over a relatively substantial distance. Alternatively, although curved-blade broadheads having a small pitch may contribute to a more desirable or expected flight path or trajectory over a selected distance, such broadheads are typically unable to effectively penetrate the targeted medium to a desirable depth; that is, the linear displacement of the broadhead through a targeted medium is accordingly reduced. Examples of such curved-blade broadheads may be seen with reference to Brozina U.S. Pat. No. 3,604,708, issued Sep. 14, 1971, and entitled “Serpentine Arrowhead;” Schaar U.S. Pat. No. 4,533,146, issued Aug. 6, 1985, and entitled “Arrow and Components Thereof;” Carrizosa U.S. Pat. No. 5,257,809, issued Nov. 2, 1993, and entitled “Detachable Rotary Broadhead Apparatus Having Drill Bit-like Characteristics;” and, Martinez et al. U.S. Pat. No. 6,319,161, issued Nov. 20, 2001, and entitled “Arrowhead and Method of Making.”
Additionally, although rotational inserts or bearing assemblies are available to assist in providing independent rotational movement of the broadhead relative to the arrow shaft when the arrow is in flight, such rotational inserts typically involve overly complex bearing systems that require unduly burdensome assembly for implementation and utilizations of same. Specifically, most bearing assemblies require the user to glue or otherwise adhesively affix a stationary bearing housing within the arrow shaft, and subsequently insert therethrough a bearing insert, or series of bearing inserts and/or surfaces, typically retained within the bearing housing via lock washers, curved washers, retaining clips, pins, interlocking channel-and-groove assemblies, combinations thereof, and the like. Of particular concern when assembling such bearing systems is the potential for accidentally or unknowingly gluing or adhesively affixing rotational components of the bearing system to fixed components therein, or to the inside of the arrow shaft. For instance, insertion of the bearing housing, or other similar components, into the arrow shaft inherently exerts pressure on the glue, and thus, may push the glue upward and out of the shaft end, and/or downward into areas that may come into contact with the rotational inserts and related components; thus, affixing same upon insertion therein. Although some types of glue may be reheated to release the bonding capabilities thereof, to permit subsequent reassembly of the bearing system, such a task is often burdensome, overly messy, time consuming, and potentially deleterious to the arrow assembly. Examples of such bearing systems may be seen with reference to Sprandel U.S. Pat. No. 3,910,579, issued Oct. 7, 1975, and entitled “Swivel-Mounted Hunting Arrowhead;” Schaar U.S. Pat. No. 4,533,146, issued Aug. 6, 1985, and entitled “Arrow and Components Thereof;” Tone U.S. Pat. No. 4,534,568, issued Aug. 13, 1985, and entitled “Archery Arrow With Freely Rotational Broadblade Arrowhead To Avoid Windplanning;” Winters U.S. Pat. No. 4,671,517, issued Jun. 9, 1987, and entitled “Apparatus for Rotatably Mounting Arrowheads;” and, Carrizosa U.S. Pat. No. 5,257,809, issued Nov. 2, 1993, and entitled “Detachable Rotary Broadhead Apparatus Having Drill Bit-Like Characteristics.”
Furthermore, apparently absent from the prior art is a bearing insert and assembly adapted to interchangeably receive a selected arrowhead, yet provide the requisite protection for the end of the arrow shaft to prevent cracking, splitting or damage to same when the arrow and arrowhead ricochets off of or otherwise impacts a target or surrounding surface. Also absent from the prior art is a broadhead having an optimized pitch to interface rotatably with such a bearing insert and assembly.
Accordingly, it would be advantageous to provide a broadhead-type arrowhead having superior flight, penetration and performance characteristics achieved through the use of pitch-optimized spiral-shaped, curving or twisting, blades of increasing width as measured from the leading edge thereof to the central axis of the arrowhead. It would be further advantageous to provide a broadhead-type arrowhead for use in association with a bearing assembly or insert to provide independent broadhead rotation with respect to the arrow shaft, wherein assembly of the bearing insert may be implemented without occurrence of the above-discussed disadvantages, and wherein the bearing assembly further functions to protect the end of the arrow shaft from cracking, splitting or damage resulting from in-flight impact against an object.